Backwards Day
by robbiepoo2341
Summary: The Avengers aren't acting like themselves at all . . . and they're wearing the wrong costumes! Tony and Bruce seem to be the only ones unaffected, but Tony is quite sure there's a logical explanation. Meanwhile, the other Avengers are all in on the plan. Bruce has made the costumes. Clint and Natasha did the planning. Steve talked to JARVIS. All that's left is to play the game.
1. Chapter 1

A/N: This is based on a text post on tumblr by tygermama that I expanded on and it made Carly happy and I like things that make my friends happy when they've had bad days so I expanded it even more.

This is a total fluff fic of hilarity :)

Disclaimer: I don't own Marvel or the Avengers.

...

Tony _knew _something was going on.

It wasn't just the fact that no one had been down to his workshop to bother him yet that morning. And it wasn't just that JARVIS hadn't interrupted him yet to inform him of the latest in-fighting disaster (usually involving Clint _why would you provoke the super humans you moron_ Barton).

The thing that tipped him off was the fact that the coffee pot was empty and, well, _cleaned_, and the breakfast dishes had been cleaned meticulously, the way Natasha liked them done, and there was no one standing around demanding praise for a job well done.

Must've been Steve.

But if it'd been Steve, Tony thought maybe he'd still be around, trying to organize a cleaning brigade, because when that man snapped and started cleaning, he seemed to think everyone else should also have gotten fed up with the state of the tower.

But no, there was nobody.

And then, very suddenly, there _was _somebody, and that's when Tony _knew _this was wrong, because why was Natasha wearing _that_?

And _smiling_.

Smiling and humming and this was very bad she was probably planning something awful Tony should really get out of there now—but he couldn't get his feet to leave because even weirder than the smiling and humming was the fact that she was wearing Captain Freaking America's costume.

It actually fit her pretty well, like it had been designed with her in mind, and suddenly Tony understood why no one had bothered him for the past however-many-days he'd been in his workshop.

Maybe it was an elaborate prank. Natasha seemed the type. Every once in a while, she'd come out with something outlandish that was both genius and terrifying, and those were her more harmless pranks.

But that wouldn't explain the smiling and the humming and the fact that when she looked up at him, her entire face lit up like she was _pleased _to see him.

Natasha had popped up from behind the island in the center of the kitchen, holding a carton of eggs and emerging with a frying pan in her other hand and a spatula between her teeth. "Oh!" she said through the spatula, setting everything down on the counter. "Hey, Tony. Long time no see." She grinned at him.

It just looked so wrong. It wasn't just the smiling or the relaxed and easy posture or the way she stood with her feet spread and arms crossed in a way that made the costume even more fitting or the fact that her hair was pulled back in a ponytail, which he'd never seen before, or the fact that she wasn't even wearing makeup when she usually looked like the Natalie-edition Tokyo model even if they'd just got the call two seconds ago and she'd been asleep when it happened.

It was everything about her. The posture, the way she seemed to be slightly off in her center of gravity, the way she treated everything like it was too big, like reaching too low for the fridge handle or the cabinet drawers.

"I know there's a story here, and I bet you're going to tell me what it is," he said carefully. That seemed like a safe thing to say.

Natasha laughed, and it wasn't her usual hum-that-sort-of-qualified-as-a-laugh or the I'm-pretending-not-to-giggle-but-my-shoulders-are-moving that Clint could sometimes get out of her (and occasionally Steve and also more often Sam than Steve). It was a full-bodied laugh that reached right up to her eyes. "Yeah, sorry, we weren't sure if you and Bruce had switched, and, well, best not to risk it if the Hulk's mind has been somehow transplanted into that evil lair of yours."

"Evil lair?" Tony repeated. "I'm shocked, Widow. Shocked and hurt." And then the rest of the sentence settled into his mind, and he realized what it meant. "Wait . . . ."

She laughed again and waved at him with a little finger wiggle. "Oh, so you're caught up. Yes, hello, Tony. What do you think of the new outfit? Turns out SHIELD has a contingency plan for every single possibility." She looked down at herself. "I think it's a pretty nice fit, though I'm not as thrilled about being short again."

Nope. No. Wasn't happening. Tony could feel his brain shutting down. Input unacceptable.

"You should see Hawkeye," Natasha (Steve?) said, and the laughter never left her eyes.

"I'm not sure I want to ask," Tony said. He shook his head again. "You didn't come get me?"

Natasha shrugged. "Thor says it'll wear off eventually. Some Asgardian's idea of a prank." She grinned down at herself. "You should see the one they made for Natasha with a heart piece just for you." She laughed again, and that was downright _unsettling_.

"How come I didn't get . . . pranked?" Tony asked. Still processing. Too weird.

Natasha shrugged. "We all went out for food while you and Bruce were . . . ." She waved her hand. "Whatever it is you and Bruce do when you're both locked up in your separate labs." She sighed. "We woke up this morning and . . . ." She laughed again. "It really is weird. You're taller than me."

"Hey," Tony said. "Now you know how it feels."

"I already knew how it feels," Natasha said carefully, and he could just _see _Steve, the way he'd drop something like that on his teammates that made you remember, oh yeah, this guy used to be tiny and bullied and frail and still oh so very Steve Rogers—the way he'd drop it on you and then shrug like the whole thing was no big deal when it _was_.

And yep, there was the shrug, and she (he? this was confusing) went right back to making scrambled eggs, with just a bit of cheese thrown in (the way Sam made them; Steve had decided cheesy eggs were the best eggs after his breakfast at Sam's).

Tony opened his mouth to say something, anything, to offer to take a scientific look at this "magic" stuff, since he didn't believe there was anything magic could do that science couldn't fix, but then he saw something move in the doorway, and, okay, yeah, wow, this day was getting too weird.

Because there was Thor, peeking out almost . . . timidly. Which was not a word Tony usually associated with the big guy. And Thor looked around the corner until his eyes fell on Tony and Natasha, and he waved Tony over with a tilt of his head and went back to hiding in the doorway.

Tony raised his eyebrows at Natasha, who just shrugged good-naturedly and went back to humming the theme song to _M*A*S*H, _the latest television show Steve had been watching after his morning workouts. (It came on the oldies channel at around 5:30, so it was perfect for cooldown eggs and orange juice, Steve had assured him.)

Tony came around the corner to see Thor, who looked frankly ridiculous. Hawkeye's suit has always been, well, the least supersuit-y. Like a more comfortable Black Widow suit, but with more purple. And on Thor? Well, Tony was used to seeing the guy in flashy metal and a cape and other Viking things, so the come down was, well, it was weird, to say the least.

"Have you seen Nat?" Thor asked quietly.

Tony looked back into the kitchen. "Depends what you mean," he said carefully. "Which one is she now?"

"I am she," Thor said, then shook his head. "I mean, she is me. Err, well . . . ." He trailed off and put a hand sheepishly to his head. "If you see me, that is, Hawkeye, and I'm still wearing Natasha's—"

"No." Tony put both hands up. "No. No _way _am I living in a tower with Clint Barton in the Black Widow suit. Nope. Nu-uh. Not happening."

"He pulls it off quite well," Thor said, his eyes twinkling. "That is, _I _do." Thor shook his head. "Magic." He said that last word like a curse.

Tony noticed the bow in Thor's hands and the quiver strapped to his back. "You sure you want to be using those?" he asked. Things might be crazy around here, but he knew Clint wouldn't risk breaking his favorite toys. "You've just super strength-ed up, there, Clint. You pull too hard, and—"

Thor waved his hand impatiently. "It's my toughest bow. I could hit you with it in your armor, and it would leave a dent on _you_."

"I doubt it."

"Would you like me to try it out when I'm," Thor paused, grinning as he repeated Tony's words back to him, "'super strength-ed up'?"

Tony made a face. "What are you hiding from Natasha for, anyway?"

Thor grinned, a big, goofy grin that didn't really belong on his face, because it was the kind of grin that said _I'm causing trouble and enjoying every second of it_. It was a Hawkeye face, and Tony didn't like the idea of all that power in Clint's hands.

"Never mind," Tony said quickly. "I don't want to know."

But Thor answered him anyway: "She seems to be under the impression that I would not prank my own body." He shot Tony his best angelic face.

"Barton, you've got a death wish."

Thor grinned, and for a moment, he looked like normal Thor, the guy who enjoyed just absolutely everything. And then he swung into the kitchen and onto the counter, dangling his legs over the side.

Tony sighed. "I'm going to go talk with Bruce, see if we can't figure this out. If you could all try not to do anything even weirder than what's already happening, that'd be great."

"No promises!" Thor thundered after him.

…

"He's gone?" Natasha asked.

"Yes, I believe he is," Thor said.

Natasha allowed herself a real smile—not a Captain America one, but her own—as she perched on the counter beside her frying eggs. She'd spent the whole morning cleaning the kitchen so she'd have an excuse to be the first one Stark saw, but it was entirely worth it to see the look on his face.

"You are quite a convincing Steve Rogers," Thor noted with an approving smile.

Natasha laughed. "And I almost bought your Hawkeye!" She crossed her legs. "But you've got to work on the accent."

Thor leaned forward conspiratorially. "Doctor Banner has already offered his help with that."

…

Tony knocked on Bruce's door.

"No, Clint, you can't come in. And if you break the door one more time . . . !"

"It's me!" Tony shouted.

"Oh," Bruce said. Then, "Good. Hold on."

Tony heard some rustling noises and then the turn of the lock, and the door swung open. "Sorry," Bruce said quickly, "I thought you were—"

"Yeah, I know," Tony said. "So."

"So," Bruce agreed.

"Body-swapped Avengers," Tony said.

"Yeah."

"I didn't think we'd be seeing this until at _least _after we all got turned into, I dunno, frogs or something," Tony said, trying to keep the mood light.

Bruce nodded absently. "I've run all the usual scans, Tony, and a few more that JARVIS helped me with." He motioned with one hand without looking to the charts lying haphazardly around the office. "That's the thing, Tony. By all rights, _nothing happened_. Brain waves are even the same, which explains Clint."

"Which one?"

"The one inside Thor. Still talks kinda like an Asgardian—or hadn't you noticed?"

"I was a bit preoccupied by the fact that Thor was _hiding _from someone," Tony admitted.

"Oh?" Bruce looked interested. "Hiding from who?"

"Natasha. Or Clint. Whoever she is," Tony said, waving his hand.

"Confusing, huh?" Bruce grinned.

"Banner, I just spent my morning in the kitchen with a smiling and laughing Natasha who was running around the kitchen humming show tunes," Tony said. "I don't think I'm ever going to recover, and I could buy the most expensive therapists this side of the world."

Bruce raised both eyebrows. "This I'll have to see."

"I'll have JARVIS play back the mansion security footage for you. It was terrifying."

Bruce shook his head and started to stand. "This is something I'd have to see in person."

Tony grinned. "Need a break?"

Bruce nodded, taking his glasses off and rubbing the bridge of his nose. "I've got JARVIS running some numbers right now." He paused. "I've told you how much I love JARVIS, right? I love him." Then, he sighed, "But I'm telling you, Tony. I think Thor's right. There's nothing we can do but wait this one out."

Tony made a face. "Now you sound like the school nurse when I got the back-to-school flu."

Bruce laughed. "Thanks, I think. But it's a good analogy."

Tony laughed. At least, if nothing else, this whole thing was putting Bruce in a good mood. And a happy Bruce meant he was more amenable to experiments that he usually said no to.

He opened the door and very nearly walked right into Clint, erm, Natasha.

It was every bit the disturbing picture he thought it would be. More disturbing still because Clint filled out the costume like it'd been made for him. And he kept everything, right down to the low zipper that peeked at his pecs.

Weirder still was the stuff that _wasn't _Black Widow's outfit on Clint Barton (which, okay, that was weird enough as it was, and there were still _weirder _things?) Weirder still was the stuff he was covered in. Lots and lots of little yellow feathers and . . . was that tomato soup? With little onion peels and bits of crackers and it was in his hair, and some of it had even seeped down into the undone zipper area.

"Natasha," Bruce said as if nothing was at all happening.

"Bruce," Clint said back. It was weird, coming out of Clint Barton's mouth, because it sounded just like Natasha, the biting, calculating, careful way she said everyone's name when she wasn't (in her rarer moments) accidentally relaxed around them.

"Umm," Tony said. This was always hard. Asking Natasha what Clint had done today. Those two had always had a weird relationship, something akin to the little boy putting his crush's pigtails in his chocolate milk or the little girl who only likes boys who can keep up with her in dodgeball. But then, Natasha always said love was for children. And Clint was the only human being that could evoke, in Natasha Romanoff, something that could almost be described as "childishness."

"Where is he?" Clint asked Tony. Curt and cut off and very annoyed. Yep, Natasha.

"Uh." Tony weighed his terror of Natasha against his terror of Clint Barton in an overpowered body. Natasha won out. "Kitchen," he said.

"Thanks." And with that, Clint had stormed off.

Bruce stared after Clint. "I don't think I want to know," was all he said.

"Yeah. I know I'm the genius around here—well, including you when you're not big and green—but that man is an _artist_."

"Remind me why you invited all these people to come and live under the same roof."

"Saves time having to call them? Or don't you remember when the Mandarin blew up my house and not a single one of you came to help?"

"In my defense, I was—"

"Yeah, I know." Tony waved his hand impatiently. "Still. It sucked. A lot."

"I heard."

Tony sighed. "We'd better go stop her from killing Clint. And Thor."

"I didn't think Thor could be killed."

"It's Natasha. She'll figure out a way."

….

"Quick. Out the window before they get here," Clint said, bursting into the room and wearing his biggest grin.

Thor and Natasha paused to take inventory of his frankly magnificent masterpiece. He'd been thorough. A little bit of every food that he couldn't find stocked in the pantry, just to keep Tony wondering how he'd gotten his hands on it. Plus the noodles in his boots. Clint couldn't _wait _to see the look on Tony's face when he started pulling those out.

"You've outdone yourself this time," Natasha said with just the barest hint of a smile. He was always pleased when he could get that smile.

"Thanks." Clint grinned. "Okay. Yep. Out the window. C'mon, Thor."

Thor grabbed Clint around the waist and jumped out of the window. He didn't have his hammer, but he did have his super strength, so he landed easily on the ground. Hardly even rattled Clint.

"Okay, here's the plan," Clint said. "Can you get us to the roof?"

"Steve Rogers has Mjolnir," Thor pointed out.

"Yeah. Slight delay." Clint chewed his lower lip thoughtfully. "Okay. New plan. How high can you jump?"

…..

Tony wondered into the living room and sighed deeply.

At this point, nothing could surprise him. Not even the sight of Steve Rogers in full Thor uniform curled up on the couch watching the scifi channel surrounded by six—no, wait, seven—empty cartons of ice cream, with an eighth halfway gone.

"Okay," Tony said, surveying the scene. Steve Rogers binge-eating, Natasha humming happily and practically skating around the kitchen . . . and a big, gaping hole in the windows. "I'll start with the less dangerous question first. I'm gonna guess you're Thor?" he asked, pointing at Steve.

"I have fallen!" Steve wailed. "This mortal form is nothing against the might of our foes!" He kicked at Mjolnir, which just kind of lazily moved aside for him. "This is just like what happened in New Mexico, but at least then I knew the feeling of my own two hands!"

"Yep. Thor." Tony sighed. "I live in a house full of babies."

Behind him, Bruce snorted. "You sure you didn't get caught in the body swapping? That was a Natasha-worthy comment."

Natasha raised a single eyebrow and looked almost like her old self, but then she laughed out loud. "Don't let her hear you say that."

Bruce turned a funny color.

But then Tony was distracted by the loud clamor coming from the already broken window.

And then a very annoyed Thor dropped down a few stories and bounced back up. Looked like his ankle was tied to one of Hawkeye's grappling ropes.

"NATASHA!" Thor yelled as he swung.

"You total _idiot, _Clint!" Clint shouted back.

"This is really weird."

Natasha sighed. "I'll do it. I'll talk her down." She stuck her head out the window and grabbed a swinging Thor. "Natasha!" she shouted up at the roof.

"Yes, please, please talk her down, Steve," Thor said, still swinging.

"Hawkeye, we're going to talk later about how you get yourself in these situations," Natasha said severely.

"That does not seem like a conversation I want to be a part of," Thor said. It was almost comical.

Hawkeye swung down using the rope Thor was still dangling from as his line. "I don't think he's aware of just what I could do while I'm in this body." A slow smile spread over his face. "Thor, let's go to the tattoo parlor!"

"No!" Thor bellowed. "I like me the way I am!"

Steve looked up from his ice cream. "This could be quite enjoyable."

Tony held his hands up, feeling even more like a babysitter. "No one is leaving this Tower until we get this figured out!"

"Just you try and stop us," Steve said, vaulting over the back of the couch. He made a grab like he wanted to take Mjolnir with him, then sighed.

Hawkeye brushed past Tony, followed closely by Natasha and Bruce, who assured Tony that he would try to "talk them down."

Thor managed to cut himself down at last, and the crash from the ground below must have been him falling. But he didn't seem to have hurt himself, because Tony could hear him calling after his teammates, "Stop! Wait!"

…

"So," Bruce said casually as he bit into his ice cream cone, "what did you get?"

Hawkeye grinned and took off his boat, rolling up his pant leg to show off the new spider tattoo at his ankle. "Been meaning to get one anyway," he said, winking suggestively at Natasha, who rolled her eyes.

"I cannot tell sometimes if you two are acting or if you are truly pledged to each other," Thor said from the front seat.

Bruce grinned. Good ol' Thor. Could be counted on to say what everyone was thinking.

"I wasn't going to say anything," Steve said. He was driving, so his ice cream cone was sitting in the cup holder.

"It's really not that complicated," Natasha said without even looking up. She was admiring the ink on Clint's ankle. Bruce suspected but didn't know for sure that Natasha had drawn it herself. She smiled the half smile that Bruce knew could get Clint to jump off a cliff if it meant another one of those smiles as she added, "Everyone blows off steam somehow. Clint and I have an . . . arrangement."

"Yeah, she likes to keep me in reserve in case she ever breaks out with a bad case of emotions," Clint said with a straight face.

"And he's needy and clingy, so I humor him," Natasha shot back.

Bruce laughed and held up both of his hands to stop the bantering. "Right, right," he said quickly. Then, because the subject needed changing pretty badly, he asked, "What do you think Tony's doing right now?"

"Having JARVIS run tests," Steve said. And Bruce would have said he sounded smug, but smugness wasn't really something that one attributed to Captain America.

"What'll he find?" Clint asked.

Steve grinned. "JARVIS and I . . . we have an arrangement."

"See, and people think _you're _scary," Clint said, gesturing to Natasha. "But give Steve half a chance and he's an evil genius."

"He's been under my careful tutelage," Natasha said.

"That is truly worrying," Thor said seriously.

Clint zipped up his boot again and looked like he might say something ridiculous (that man was simultaneously one of the most intelligent and most idiotic men Bruce had ever met, and that was saying something), but a blinking light in the car caught their attention, and JARVIS's voice in the override said, "Avengers, we have, ah, a slight problem."

Bruce smiled. Only Tony Stark would design an AI that could _hesitate_ like that.

"Don't tell me," Clint sighed. "Assembling time?"

"The Wrecking Crew is downtown, and—"

"No problem," Natasha said, and Bruce could practically see the wheels in her head turning.

"I believe now would be the perfect time to end this ruse and—"

But Clint had his Natasha-and-I-are-on-the-same-page grin, which was a downright terrifying grin, and he said, "No, this'll be great. We'll run a quick costume change, everyone back in their normal spots, and tell Tony we didn't want the bad guys to know we were vulnerable."

Bruce tilted back his head and groaned. "I'm going to end up having to carry your weight, aren't I?"

"You're the one who helped us design the costumes, Bruce. You're complicit now," Clint said with a grin.

…

"Clint, you can't keep the high ground. You have to do hand to hand," Clint said, and oh, wow, it was really weird to hear Clint give himself orders in a Natasha-style commanding voice.

"Fine," Thor said, a perfect pouting Hawkeye as he landed in the middle of the street.

"HULK TIRED OF BACKWARDS DAY," shouted the big green guy next to him. Hulk had been doing a lot of the muscle work for them in their fight. Not that it seemed to bother him.

Tony put a repulser ray in one of the bad guys' faces—didn't much matter who—and patted the Hulk on his elbow. "Yeah, I know. It's crazy fun times around here, huh?"

Hawkeye was busily rolling around, dodging and ducking and getting as close as possible before he shot his arrows. Dead center, of course, but Tony had long suspected that Clint had been teaching Natasha how to handle a bow when they were . . . off doing whatever it was they did together.

Natasha was pulling off some unusual gymnastics and sucker punches. Fought like a soldier without her usual finesse. Lots more brute force.

Steve fought with . . . abandon. Grinning and shouting at the world what a wonderful fight this was and using his fists more than his shield.

Hulk was ultimately the one that finished off the Wrecking Crew, but the team performed well. Natasha was right; no one could have known that they were really this vulnerable.

….

"How long are we going to keep this up?" Thor asked as they watched Tony skulk off to his workshop.

"I dunno," Clint said, leaning back with his hands behind his head, "I was thinking I'd like to try and throw the shield. No reason for Nat to have all the fun."


	2. Chapter 2

A/N: I guess I'm expanding this! ;)

Disclaimer: I don't own the Avengers or any of the related rights.

...

This was almost too good to be true.

Loki watched in quiet glee as the Avengers paraded along in front of him—well, most of them, anyway. He could tell they weren't under any spell, that they were still themselves, so this had to be an elaborate prank of some kind.

And since this world knew him as a god of mischief, he felt he should do his godlike duty and approve their actions. Make them a little more permanent.

He did not see the monster or the self-proclaimed genius with them. Perhaps they were the intended target of the trick. Loki debated quietly waiting for the team to return to their precious Tower before he attacked, but his brother was without Mjolnir, and Loki did not know when another such chance would come.

They'd practically laid out a welcome mat for him.

He waited until they were all piled into one car before he threw one of his illusions onto the car's dashboard, perched with legs crossed and an interested expression.

And when his brother threw out his hand to call for Mjolnir, Loki knew his soul was still in the right body.

He didn't have much time to make the switch, so he hurriedly stopped the car and locked all exits. "And here I was debating how best to ruin my brother's day, and you have all so graciously given me exactly the tools I needed."

The woman reached right into a pocket in the outfit her partner wore and pulled out a gun, though she didn't seem all that surprised when the bullet passed right through Loki. Very little could rattle that woman.

"Brother!" Thor thundered. "What are you doing here?"

Loki waved his hand. "If I stopped to tell you that, your precious hammer would arrive before I finished my tale. So," he said, stretching his legs, "right to business."

…

Tony looked up in surprise when Mjolnir rocketed out of the window. The others had only been gone for twenty minutes to meet up with one of Thor's Asgardian friends (though Tony was starting to suspect that was just an excuse for them to get out of the Tower and away from Tony's monitoring systems—they'd all been suspiciously chummy).

Whoever they met must have switched their bodies back to normal, then, if Mjolnir was anything to go by.

But then one of his alarms was going off, the panic alarm he'd installed in every car in case they were attacked on the streets—which, surprisingly, seemed to happen to them a lot, when really, shouldn't the bad guys have learned by now that attacking one Avengers called down the wrath of the rest of them?

Tony called his armor to him and was only partly clad when the bits and pieces suddenly stopped in mid-flight. He could _see _them, but they weren't moving.

That's when Loki showed up, and Tony knew something had definitely gone wrong.

Loki looked disdainfully over at the half of Tony's armor that hadn't quite made it, then at Tony. "You mean to help your friends when they have been so dishonest to you?" he asked quietly, but in typical Loki fashion, he didn't bother to follow up that statement with anything that resembled rational explanation. Instead, he waved his hand, and Tony found himself somewhere else. Somewhere very different.

Crap.

…

Bruce had only closed his eyes for a second, but now that he opened them, he seemed to be in the Avengers' living room, and Tony's armor was headed right for him!

The faceplate smacked into place over his face, and Bruce sighed at the enclosed space. "Tony," he said, "I don't know what you're up to, but this . . . ." He trailed off.

"Oookay." He watched as the helmets internal systems lit up with life, showing him readouts and information and a playback function. Yep, that was what he wanted.

Bruce was almost too scared to look at anything that wasn't the internal systems, because he didn't much want to think about why he sounded like Tony Stark.

"JARVIS," he said, still sounding very much like Tony, "can you hook me into the Tower's security systems? Play back the last few minutes so I can see what happened?"

"Yes, sir," JARVIS replied, which was weird.

And as Bruce watched, he knew there was no getting around it. He saw Loki, he watched the transformation from the outside, but that still didn't make it any less weird.

He felt the Tower tremble and saw rubble falling. He threw up his hands instinctively and mentally clamped down on the Other Guy, waiting for his automatic defense system to kick in and turn him green . . . but it didn't happen.

"This isn't good," he said, and for the first time in a while, he let himself panic at the danger he knew he was in.

…

Natasha put her hands up in front of her face, shielding her body against the glass as she crashed through it. She'd been going a lot faster than she'd anticipated, and once she crashed through, she looked back down at a very embarrassed-looking Clint (in Thor's body). "Sorry!" he shouted up at her.

Well, she _had _asked for a boost.

Natasha brushed herself off, surprised by the soreness in her arm where she'd landed. Clint had fallen pretty hard on his side in their last mission, but he'd sworn he was okay. If the throbbing was anything to go by, he was a dirty liar, and she should have known better, but he'd been able to shoot his arrows no problem, and so she'd brushed it off and figured he could kid himself for a while longer as long as it wasn't serious. Besides, she'd had a prank to plan.

The Hulk was freaking out on the top floors, but so far, he hadn't left the Tower. And he and Hawkeye had come to an understanding forever ago, back when the Hulk first surfaced accidentally, just a few months after New York and the Chitauri, when some idiot terrorist thought it would be a good idea to bomb the still-under-construction Tower to delay the Avengers assembling for a little longer.

The Hulk came out, and Hawkeye had just strolled right up to him, stood in his path with his arms crossed, and told the Hulk to "Calm down, you moron."

Natasha wasn't sure she could do what Clint could do. The way he treated the Hulk like an annoying little brother or an old roommate who got mad when you left too many dishes in the sink. But she knew the Hulk recognized Hawkeye, and so maybe this was worth a shot.

Clint was coming in after her as Thor to cover her back—he always had her back—but she'd asked that she try flying solo first.

"Aren't you scared?" he'd asked.

She hadn't answered, because he should have known better than to ask. Of _course _she was scared. The Hulk was one of the few forces in this world that could actually terrify her, and she'd seen personally what he was capable of. She didn't know how Clint could antagonize and tease the Big Guy unless he had a death wish (which, thankfully, she knew he didn't—he was just a moron).

But Clint should have known better. He wasn't supposed to call her out on anything that resembled weakness.

She turned the next corner and found Iron Man splayed out on the floor. He looked like he might be unconscious, and his arm was bent at an angle that definitely couldn't be good for him. Half the armor was missing from that arm, too, and it looked like it might have been torn right off.

Natasha started towards Iron Man, but a deep rumbling just beyond Iron Man stopped her.

And then he was there. The Hulk. Angrier than she'd seen him since the time he thought the Wrecking Crew had killed Clint (to be fair, they'd very nearly succeeded, but Clint had more lives than a cat and also didn't seem to mind hiding in really tight places that he shouldn't have been physically able to squeeze into).

But the surprising thing was what the Hulk was shouting: "_MY _ARMOR! GIVE IT BACK."

….

Clint really wished he could fly. That might at least have made up for the fact that everything was way too soft and easily broken around him.

He heard the Hulk shouting and pushed Thor's body a little bit harder. Natasha's plan was sound, yeah, but half the secret of calming the Hulk down was throwing him off the rage by annoying him. It was counter-intuitive, but it worked. If the Hulk was distracted by the surprise of a "puny human" standing toe to toe with him, that moment of distraction was enough to let the thinking side kick in.

The Hulk wasn't a mindless beast, after all. He could take orders just as well as he could take a hit. He just needed a moment to remember that mind.

Clint was almost caught up with Natasha when he heard the crashing and paused long enough to catch part of the falling ceiling—yeah, that was weird—before he heard, "_MY _AMOR! GIVE IT BACK."

Oh.

Oh no.

Clint pushed himself even harder and crashed right through the wall (which only sort of hurt, sort of like crashing into a training dummy) into the path of the rampaging Hulk. He took the scene in with just a glance: Natasha standing there in his body, her jaw clenched in her "coming up with a new plan that better fits these circumstances" expression; Iron Man splayed out on the floor with one arm missing its armor; the Hulk standing there with pieces of that armor crushed in his fist.

"Cool it, Big Guy," Clint said, jumping in between the suit, Natasha, and the Hulk.

For a moment, the Hulk paused. Then, baring his teeth, he said, "LOKI."

"Yeah, yeah," Clint said, slowly making his way towards the Iron Man suit. "We saw him earlier. Made the body swap a permanent thing." Better not say anything about how the whole thing was a prank, or the Tony Stark version of Hulk might get even more angry.

"LOKI TOOK MY ARMOR AWAY."

"Almost right," Clint said. He knelt down beside Iron Man, but that got a big Hulk scream, so he stood back up quickly. No matter. He'd checked for a pulse in the exposed arm, and it was there. Faint, but there. "He put you in Banner's body, Stark."

"PUT ME BACK."

"Sure thing, Stark. But if you want out of there, you're going to have to calm down."

That was definitely the wrong thing to say. "NO CALM DOWN. FIX STARK," Stark-Hulk shouted, and then he punched Clint.


	3. Chapter 3

**Disclaimer: I don't own the Avengers or anything else Marvel related. Also, the Hulk's internal voice is hilarious in my head.**

...

"That is a strange sight to see from the outside," Thor mused, watching as Hawkeye—in his body—fell from the top of the Tower.

"Shouldn't we step in?" Steve asked. He fiddled around in the Black Widow's pockets, trying to find something useful, but he found only more weapons. "I'm sure she's got a cable launcher in here or something," he muttered quietly.

Thor frowned as he heard the roar of the Hulk from far above them. "I fear we would only get in the way here," he muttered. "Our mortal frames cannot take the punishment that our friend above us can inflict."

"Since when has that ever stopped us?" Steve asked, a look of grim determination marring the Widow's otherwise pleasant features. It was strange that Steve's presence in her body could elicit such warmth and beauty. The Widow was already beautiful, but Steve's gentle spirit only magnified that.

"You do have a point," Thor grinned.

Steve let out a "ha" of triumph as he fished out the cable launcher he had been searching for, and the cable embedded itself into the Tower. He held out a hand to Thor. "Want a lift?" he asked with a sly smile.

"Should I not be the one to carry you?"

Steve rolled his eyes. "Just hold on," he said.

….

Tranquilizer arrow. There was a tranquilizer arrow somewhere in Clint's quiver, and she knew it worked on the Hulk. Sometimes it took two or three, but they worked, at least enough to slow him down so they could reason with him.

She just hoped that it would work on the Stark version as well.

Natasha sighed. "Clint, you moron," she hissed through gritted teeth. "How do you ever find anything?"

She'd make him sit down with masking tape and a Sharpie to label all these things next time she had the chance.

Stark-Hulk had returned to the armor, but at least this time he wasn't tearing frantically at it, trying to pull it off of Bruce. That was good. Bruce needed the breathing space.

"BANNER?" It was actually a relatively quiet question, for the Hulk, though it echoed in the silence of the rubble around them.

The silence after that question was terrifying, even though it only lasted a few seconds. Natasha pretended she didn't sigh in relief when she heard the quiet, gentle, "Hiya, Tony."

The Hulk also seemed to relax when he heard Banner's voice, even though it was technically Tony's voice. "BANNER HURT?" he asked.

"Yeah," came the muffled response. "Not your fault, though, Big Guy."

Now, _that _was an interesting response. It was like there were two different people warring for control of the Hulk's emotions. Like there was a monster and Tony at the same time, but the monster . . . was different.

Natasha had seen the Hulk plenty of times up close. She knew him pretty well, and she knew that the "Other Guy," as Bruce called him, was really a personality of his own. He was separate from Bruce Banner, and yet they were the same person.

So, how much of the Hulk was left behind when Stark inherited the Other Guy?

…

Banner recognized him. The Other Guy.

And yeah, sure, Tony was in there, too. He was just behind the angry glare. But that was his Hulk. His Other Guy. And he had to deal with Tony's anger issues now instead of Bruce's, and Bruce could tell it was hitting the Other Guy pretty hard.

He tried to push himself up, to look the Hulk in the face, but he couldn't quite move. He'd be content with just lifting the faceplate a little higher. "Hey. Hulk," he said quietly. The Other Guy had always liked Tony, so maybe the voice would be helpful.

The Other Guy lifted his head, tilting it slightly. Bruce could see Natasha, in Clint's body, rummaging through Clint's arrows. He hoped she could hurry it along.

"It's okay," he said, trying to keep his voice even despite the whirling red in his vision and the searing pain in his arm. It had to be broken in at least a dozen places. "We'll fix this."

"NOW."

"Not now, but soon."

"NOW," the Hulk demanded, louder this time. Then, even louder, "NO MORE STARK."

Bruce smiled lightly. Yep, that was the Other Guy. He didn't much like being controlled, and Stark definitely struck Bruce as a control freak. He could only imagine the mental battle going on back there.

"Okay," he said. "No more Stark. Promise. As soon as we figure out how to get everyone back in their right bodies, we'll fix you first."

This seemed to placate the Hulk, and he relaxed, the tension in his shoulders dropping. "FIX ARMOR, TOO?" he asked hopefully.

Bruce forced himself to nod, but the effort made him dizzy. As his vision swam, he heard the crackle of glass nearby and the booming sound of Thor's voice. "Blue tips, Nat."

"You have _got _to find a better system," Natasha said, and Clint's voice sounded tired. Bruce blinked back the darkness and focused on the arrow in Natasha's hands.

She was a good shot, but even Bruce could see that Clint was nervous about the shot.

…

Steve pulled himself and Thor up and into the window just as Natasha fired. He watched the arrow fly, and Natasha was a pretty decent archer, but it just wasn't exactly where Clint would have put it. Right beneath the Hulk's arm, just in the fleshy part.

Steve winced, but the Hulk just turned, slowly, staggering slightly from the blow. Natasha hurriedly reloaded another arrow as Clint stepped protectively in front of him.

The Hulk narrowed his eyes, studying the pair of them. "WIDOW. YOU SHOT HULK."

Natasha looked like she would rather be anywhere but underneath that gaze, but she, to her credit, held her ground. "Yeah, well, you were smashing things. Had to slow you down somehow," she said. Her voice was soft and careless, and there was no obvious leadup to the second shot, which was much closer to Hawkeye's soft spot.

The Hulk staggered again, and Steve rushed forward. He could see Bruce lying there in mangled Iron Man armor, and the last thing they needed was for the Hulk to crush him as he stumbled. And with Clint watching out for Natasha while she had the Hulk's attention . . . .

Well, it was definitely a good thing that Steve was now small and spry. He could get around unseen if he really wanted to—he'd done plenty of covert ops for SHIELD and before that for the Howling Commandos—but Natasha made it her art, and Steve could actually _feel _the muscle memory as he crouched low, trying to stay out of sight.

He moved quickly, and he heard Thor move behind him, holding the shield so readily and easily that it already seemed like an extension of himself. Steve wondered if that was just the muscle memory of his own body working for Thor or if Asgardians had shield training as well. Either way, he was grateful for the cover. His shield could withstand a good hit, including a Hulk hit, and he felt a little safer with it around.

He'd probably ask for it back, but Thor had been so upset that Mjolnir no longer responded to his call that Steve figured he'd let Thor keep the shield a little longer. Give him a weapon he could use. It wasn't like the Army and SHIELD hadn't trained him in all the weapons Natasha had at her disposal. He could shoot a gun if he had to.

As Steve pulled Bruce out of the rubble and the pieces of Iron Man armor, the Hulk turned. So Steve hadn't been as sneaky as he should have been, but hey, he wasn't _actually _Natasha.

He braced himself for the blow, pulling Bruce with him as he dodged, hoping that the Hulk wouldn't hit anything important. But instead, he heard a loud clang and felt the floor shift underneath him, and he knew without even looking what had happened.

He looked back to see Thor standing underneath his shield, his legs and arms braced as the Hulk drew back for another punch.

"Heads up!" said a booming voice, and yeah, it was really, really weird having Hawkeye in Thor's body, because a snarky Asgardian really shouldn't have existed.

Clint-as-Thor tackled the Hulk, and the two of them went crashing through the window.

….

Blondie was different. He was different, and he was cracking jokes and dancing around so Hulk couldn't just smash him.

Hulk wanted to smash him. Hulk wanted to punch _something_, and he remembered that Thor could take Hulk's punches, so Hulk wanted to punch him.

"Whatsa matter, Big Guy? Getting rusty?" Blondie asked.

Wait. Blondie didn't talk like that.

Oh. Right. Backwards Day.

"HULK TIRED OF BACKWARDS DAY," he bellowed, frustrated as Blondie ducked out of the way once more. Widow had shot Hulk, and Hulk was slower now. Harder to hit stuff.

"Yeah, me too, but y'know, I'm sorta liking the new look," Blondie said, flipping his hair over his shoulder. "What do you think—am I the fairest in the land?"

Stark was inside him now. Stark and not Banner, and the Stark inside him was screaming, so Hulk said the words Stark was screaming: "BARTON, YOU MORON."

Blondie stopped long enough for Hulk to hit him, but he caught Hulk's fist on his arm. "That you in there, Stark?" he asked casually.

"YES," Hulk grunted. Might as well tell the truth.

Blondie's eyes lit up with laughter. "Oh, man, that has gotta be the weirdest feeling. You're gonna tell me all about it when we get Loki to change us back?"

Loki. Hulk recognized that name. "PUNY GOD DID THIS?"

Blondie laughed. "Yeah. Yeah, he did. And we're gonna put it back, okay? So why don't you sit your shiny green butt down and give us back Tony so we can get this whole thing sorted, huh?"

Hulk thought about it. He had been tired of Backwards Day before, when they were all pretending, when Blondie left his hammer at home and Cupid got too close to the bad guys he shot at. Now Backwards Day was real, and he was in it, and this prank had gone on long enough. "FIX IT," he bellowed.

"Sure thing, Big Guy," Blondie said, and that's when Hulk felt it. Just the slightest prick, right under his arm.


End file.
